Chechen militant leader Umarov reported killed

MOSCOW -- Chechen rebel leader Doku Umarov, whose Caucasus Emirate group claimed responsibility for a string of deadly attacks in Russia over the last years, has been killed, a pro-insurgency website said Tuesday.

"The leadership of the Caucasus Emirate officially announces the martyrdom of Emir Dokku Abu Usman," the Kavkaz Center website said, using the Arabized nom-de-guerre of Umarov.

It gave no details of how he was said to have been killed and there was no confirmation from the Russian authorities who are usually keen to rapidly boast of the "liquidation" of top Caucasus militants.

"Foreign media periodically publish information about the liquidation of Doku Umarov but the Russian special services at this moment do not have such information and will not comment on it," the National Anti-Terror Committee said in a statement to the state RIA Novosti news agency.